Randomized Controlled Trial of Thresholds for Drain Removal After Anatomic Lung Resection

The criteria for chest drain removal after lung resections remain vague and rely on personal experience instead of evidence. Because pleural fluid resorption is proportional to body weight, a weight-related approach seems reasonable. We examined the feasibility of a weight-adjusted fluid output threshold concerning postoperative respiratory complications and the occurrence of symptomatic pleural effusion after chest drain removal. Our secondary objectives were the hospital length of stay and pain levels before and after chest drain removal.

This was a single-center randomized controlled trial including 337 patients planned for open or thoracoscopic anatomical lung resections. Patients were randomly assigned postoperatively into 2 groups. The chest drain was removed in the study group according to a fluid output threshold calculated by the 5 mL × body weight (in kg)/24 hours formula. In the control group, our previous traditional fluid threshold of 200 mL/24 hours was applied.

No differences were evident regarding the occurrence of pleural effusion and dyspnea at discharge and 30 days postoperatively. In the logistic regression analysis, the surgical modality was a risk factor for other complications, and age was the only variable influencing postoperative dyspnea. Time to chest drain removal was identical in both groups, and time to discharge was shorter after open surgery in the test group.

No increased postoperative complications occurred with this weight-based formula, and a trend toward earlier discharge after open surgery was observed in the test group.